A variety of workpieces may be required to be cryogenically cooled for various purposes, such as during different manufacturing or inspection operations. To evaluate the bond between the metal and composite portions of a workpiece, the workpiece may be cryogenically cooled to allow the metal and the composite portions thereof to be physically separated without damaging the structure of the bond region therebetween.
In order to cryogenically cool a workpiece, the workpiece may be submerged within a bath of cryogenic liquid, such as a bath of liquid carbon dioxide or liquid nitrogen. In order to submerge the workpiece within the bath of cryogenic liquid, the bath must generally be larger than the workpiece and, as a result, may disadvantageously consume valuable floor space as a result of the bath's relatively large footprint. In order to submerge a workpiece within the bath of cryogenic liquid, the workpiece is typically transported to the bath and handled in such a manner as to be controllably submerged within the bath and then withdrawn from the bath following the cooling of the workpiece. The amount of cryogenic liquid, such as liquid nitrogen or liquid carbon dioxide, should also be correspondingly large to permit the workpiece to be fully submerged therein. In instances in which the workpiece is relatively large and/or heavy, the transportation of the workpiece to the bath and the handling of the workpiece in conjunction with its submersion within the bath may also require correspondingly large and, in some instances, complex equipment to interact with the workpiece.
A spray gun may alternatively be utilized in order to spray liquid cryogen upon a portion of a workpiece. The spray gun generally applies the liquid nitrogen on a small area of the workpiece. Accordingly, the spray gun must be continuously moved over the surface of the workpiece to cool a larger portion of the workpiece. The movement of the spray gun across the surface of the workpiece may increase the time required to cryogenically cool the workpiece and may prevent all portions of the workpiece from being cryogenically cooled simultaneously. The spray gun also generally includes a canister that provides the cryogenic liquid to be sprayed upon the workpiece, thereby increasing the weight of the spray gun. The spray gun may thus be limited by the capacity of the canister.